document.write( "Question 466930: If n and p are integers greater than 1 and if p is a factor of both n+3 and n+10, what is the value of p?\r
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document.write( "The answer is 7, but I do not understand how they got this answer.\r
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document.write( "Can you help? \n" );
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Algebra.Com's Answer #320258 by robertb(5830)![]() ![]() You can put this solution on YOUR website! p a factor of n + 3 ==> n + 3 = rp, for some positive integer r\r \n" ); document.write( "\n" ); document.write( "p a factor of n + 10 ==> n + 10 = sp, for some positive integer s\r \n" ); document.write( "\n" ); document.write( "(n + 10 > n+ 3 ==> s > r.)\r \n" ); document.write( "\n" ); document.write( "Hence (n+10) - (n+3) = sp - rp = (s-r)p, or (s-r)p = 7. (Note that s-r is a positive integer.)\r \n" ); document.write( "\n" ); document.write( "Hence p divides the prime number 7 (divisors are 1 and 7.)\r \n" ); document.write( "\n" ); document.write( "This means p = 7, since p > 1. \n" ); document.write( " |